Nine of the world's biggest investment banks on Monday formally launched Turquoise, a pan-European electronic trading platform to compete with established players such as the London Stock Exchange. Turquoise has been trading since Aug. 15 but its formal launch was held back until Monday, just days before US-Nordic stock market operator Nasdaq OMX kick-starts its own new European index. The new indices are providing direct competition to current leading players which also include the pan-European exchange Euronext and Deutsche Boerse, which operates the Frankfurt stockmarket. “Advances in technology and changes in European legislation have enabled us to create an alternative trading platform for Europe,” Turquoise said Monday on its website. Turquoise is backed BNP Paribas, Citigroup, Credit Suisse, Deutsche Bank, Goldman Sachs, Merrill Lynch, Morgan Stanley, Societe Generale and UBS. “We feel that we've just started and expect rapid growth in the coming weeks and months,” Turquoise chief executive Eli Lederman said on Monday. Turquoise started with only 10 stocks from two countries a month ago. “In just over a month now, we have added members, market-making, 11 more countries and trading in just under 1,300 stocks. Everything has gone according to plan,” said Lederman. He said Turquoise has regularly been executing trades worth between one and two billion euros (1.46 and $2.92 billion) a day. Turquoise is accounting for more than two percent of trading in the 270 most-liquid stocks that it covers and has a more than five-percent market share in over 90 stocks, added Lederman.